Slide changing device for a projector



Oct. 11, 193s. Q. w EL 2,132,716"

SLIDE CHANGING DEVICE FOR A PROJECTOR Filed March 20, 1937 FIG..1.

INVENT OR.

Patented Oct. 11, 1938 g 2,132,716 v UNI-TED STATES PATENT OFFICE SLIDE CHANGING DEVICE FOR A PROJECTOR Qtto Wittel, Rochester, N. Y., assignor to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey Application March 20, 1937, Serial No. 132,107 7 Claims. (Cl. 88-28) The present invention relates to a slide changjector may comprise a base It! into which one ing device for a projector in which the projecor more leveling screws II are threaded. A tion beam is doused simultaneously with release lamphouse l2 of conventional design and enclosof the slides for changing. ing a light source, not shown, is mounted upon It is well understood that a more pleasing effect the base Ill.

- is obtained in the projection of still pictures if An intermediate mounting frame I3 is fastened the projection beam is intercepted or doused for to the base It] and to the lamphouse |2 by a the change of slides. It is also known that transthumbscrew l4 which passes through the openparent slides may be held in a guideway of a ing IS in the top of mounting frame IS. The

projector by holding means that can be released intermediate mounting frame l3 has a shoulder 10 at will for changing the slides. l6 and is provided with an opening H.

The primary object of the present invention A guideway I8 is vertically arranged upon the is the provision of a projector for transparent projector and includesa back plate I 9 which is slides in which the holding means for the slides fastened to intermediate mounting frame l3 by at the projection opening is released by move.- bolts 20, see Fig. 5, and which is provided with 15 ment of the shutter for intercepting the proa projection opening 2|. Said guideway l8 has jection beam into closed position. a channel cross-section and comprises side walls Another object of the invention is the provi- 22 and overhanging front edges 23. An abutsion of spring members for holding a transparment. is provided at the lower end of guideway a out slide at a projection opening in a guideway l8 upon the shoulder l6 and includes a flange 25. 20

and of projections on a pivotally mounted shut- A shutter housing 2Q is fastened to intermeter. which projections engage the spring memdiate mounting frame l3 by screws 21 and is bers for release of the transparent slides when recessed at one end to fit over the guideway HIV the shutter is moved to intercept the projection and at the other end is provided with a threaded 25 beam. opening 28 for the objective 29. A square shaft 25 Other and further objects of the invention will 30 is journaled in the sides of shutter housing be evident to those skilled in the art from the 26 and carries a shutter member 3|. An oper following description. ating arm 32 is connected to one end of shaft The above and other objects of the invention 30 and is at one side of shutter housing 26. R0-

30 are embodied ina projector for transparent slides tation of said operating arm. 32 rotates said 30 which'is provided with a guideway for the slides, shutter member 3| to cover p ojection openi one or more holding members for maintaining a 2| in guideway l8 and to intercept the projecslide at the projection opening of said guideway, tion beam of the p j a pivotally mounted shutter, and dis-engaging A holding means is associated with the guide- 5 means operative, upon movement of said shutter way l8 for engaging and maintaining a transto closed position, to release said holding means parent slide at the projection opening 2|. Such which is maintaining a slide at the projection a holding means may comprise a pair of spring opening. members 33 which are fastened within inter- Reference is hereby made to the accompanying mediate mounting frame l3 by rivets 34 and 0 drawing wherein similar reference characters which include curved portions 35 extending designate similar elements and wherein: through the opening H in intermediate mount- Fig. 1 is a side elevation of a projector equipped ing frame l3 and extending through apertures with the novel features of the invention. 36 in the back plate IQ of guideway I8.

Fig. 2 is a vertical cross-section through the The transparent slides 31 may be of any known projection head of the projector.. form, such as lantern slides, or films mounted 45 Fig. 3 is also a vertical cross-section through between transparent sheet members and are the projection head showing the holding means adapted to be introduced at the top of guideway in released position when the shutter is in closed l8 and fall by gravity through the guideway.

position. According to the arrangement shown, which in Fig. 4 is a horizontal cross-section taken on no way restricts the application of the invention, 50

the line 4-4 of Fig. 3. the first slide 31a, see Fig. 3, falls onto the abut- Fig. 5 is a fragmentary rear elevation of the ment 24 of guideway l8 so that the second slide gate structure for the projector. 31b rests upon slide 31a and. is framed at the The invention is particularly applicable to a projection opening 2|. Obviously, abutment 24 projector for transparent slides. Such a prois so spaced from said projection opening 2| 55 viate this difliculty the holding means supplemented by the provision of a curved spring member 33, see Figs. 3 and 4. Said curved spring if it is riotguided through guideway l3 the superjacent slide may not abut the lower slide and may fall directly through the guideway. To obmay. e

member 38 may have one, end folded over the upper end of back plate IS, the other end folded through an opening 33, see Fig. 3, in back plate [3 and is intermediately convexly bowed toward the overhanging front edges 23 of guideway l3. Curved spring member 33 is also provided with an opening 43 in registry with the projection opening 2| of guideway l3. The engagement of the slid es 31 by spring member 33 is sufiicient to lightly urge the slides against the overhanging front edges 23 but is not sufflcient to prevent the falling of the slides through guideway |3 under the action of gravity. Spring member 38 merely insures that all of the slides will rest against said overhanging edges 23 so that the superjacent slide 31b will always abut the lower slide 31a and be properly framed.

In the modification shown in Fig. 3, the curved I portions 35 of spring members 33 bear against the side margins of curved spring member 38, see Fig. 4. Consequently, the slides may be held in position either by direct engagement of curved portions 35 therewith or by said curved portions pressing against the spring-member 38 which in turn engages with the slides and maintains them at the projection opening 2|.

The outstanding featin'e of the present invention is a co-operation between the shutter member and the holding means so that as the projection beam is intercepted or doused the holding means is disengaged from the slide at the projection opening. Such co-operation may be effected by the provision of disengaging means movable with the shutter member and for operating the holding means. trated embodiment the disengaging means are provided in the form of projections 4| which are mounted upon the side edges of shutter member 3| or formed integral therewith. Spring members 33 are provided at a slight angle so that the extreme free ends 42 thereof overhang the side walls 22 of guideway I8 and so that projections 4| may pass guideway I8 at each side thereof and strike the ends 42 of spring members 33. Projections 4| are of such length that when shutter member 3| has been moved to closed position, as shown in Fig. 3, said projections ll have moved the spring members 33 to release the slide at the projection opening. In this manner the slide at the projection opening does not move until the projection beam has been intercepted and the undesirable eifect of a moving illuminated slide is eliminated.

The shutter member 3| and operating arm 32 are balanced so that they assume a normal position, as shown in Figs. 1 and 2. In order to eliminate the noise when the shutter member 3| returns to its open position, a rubber bumper 43 is provided within shutter housing 26.

The holding means is illustrated and described as comprising two spring members 33 on the opposite side of the guideway l8 from the shutter In the specific illusguideway and provided member 3|, however, it is clear that only one spring member 33 may be sufilcient or that the shutter may be arranged on the same side of the guideway as the spring members. Other modifications of the invention may be obvious to those skilled in the art and are deemed to be within the scope of the invention as defined by the appended claims.

Having now particularly described my invention what I desire to secure by Letters Patent of the United States and what I claim is: b

1. In a projection apparatus, the combination with a stationary guideway for transparent slides and provided with a projection opening, and holding means movable into said guideway for engaging and maintaining a slide at said projection opening, of a shutter member movably mounted with respect to said projection opening and movable to a closed position for intercepting a projection beam through said opening, and disengaging means movable with said shutter member and for operating said holding means to disengage the slide at said projection opening upon movement of said shutter to closed position.

2. 'In a projection apparatus, the combination with a vertical and stationary guideway for transparent slides and provided with a projection opening, and holding means extending into said guidewayand for engaging and maintaining a slide at said projection opening, of a shutter member movably mounted with respect to said projection opening and movable to a closed position for intercepting a projection beam through said opening, and disengaging means movable with said shutter member and for operating said holding means to disengage the slide at said projection opening upon movement of said shutter member to closed position.

3. In a projection apparatus, the. combination with a vertical guideway for transparent slides, provided with a projection opening, and including an abutment at the bottom of said guideway to support a slide and spaced from said opening so as to frame a superjacent slide therein, and holding means having a part within said guideway and for frictionally engaging and maintaining a slide in frame at said projection opening against the action of gravity, of a shutter member movably mounted with respect to said projection opening and movable to a .closed position for intercepting a projection beam through said opening, and disengaging means movable with said shutter member and for operating said holding means to disengage tion opening upon movement of said shutter member to closed position.

4. In a projection apparatus, the combination the slide at said projecwith a vertical channeled guideway with overhanging edges, provided with a projection opening, and including an abutment at the bottom of said guideway for supporting a slide and spaced from said opening so as to frame a superjacent slide therein, a curved spring member within said with an opening in registry with said projection opening and for lightly urging said slide against the edges of said guideway, and a holding member extending into said guideway and pressing said spring member against a slide to hold the same at said projection opening, of a shutter member movably mounted with respect to said projection opening and movable to a closed position for intercepting a projection beam through said opening, and a disengaging member movable with said shutter memwith a support having a.projection opening, a

guideway for slides also provided with a projection opening, and provided with a hole adjacent said opening, and a spring gnember mounted upon said support and including a curved portion extending through the hole in said guideway and for maintaining a slide at said projection opening, of a shutter member movably mounted with respect to said projection opening and movable to a closed position for intercepting a projection beam through said opening, and disengaging means movablewith said shutter member and for operating said spring member to, disengage the slide at said projection opening upon movement of said shutter member to closed position.

6. In a projection apparatus, the combination with a. support provided with a projection opening, a guideway for lantern slides and provided with a projection opening, and holding means upon said support on one side of said guideway, having a portion extending into said guideway for maintaining a slide at said projection opening,

and having a second portion extending beyond the edge of said guideway, of a shutter rotatably mounted at the other side or said guideway and movable to a closed position for intercepting a projection beam, and a projection on said shutter so located that upon movement of said shutter to closed position, the second portion of said holding means is moved and the first portion thereof releases the slide at said projection opening.

7. In a projection apparatus, the combination with a support provided with a projection opening, a vertical channeled guideway with overhanging edges, provided with a projection opening and with a hole on each side thereof, and including an abutment at the bottom of said guideway for supporting a slide and spaced from the opening in said guideway so as to' frame a superjacent slide in said opening, a. curved plate spring member within said guideway and provided with an opening in registry with said projection opening and for lightly urging the slide against the' overhanging edges of said guideway, and a pair of spring members on said support at each side of the opening therein, each having an intermediate curved portion extending into each hole in said guideway normally to press against said plate spring and hold a slide at said projection opening, and each having an end portion extending beyond each edge of said guideway, of a shutter housing attached to said support, a shutter mounted within said housing for rotation about an axis transverse to said guideway, and a projection on each edge of said shutter, located and proportioned to engage the end portions of said spring member when said shutter is moved to cover the projection opening in said guideway and to move said intermediate curved portion away from said plate spring member so that the slide at the projection opening may drop onto said abutment.

' O'I'I'O WI'I'I'EL. 

